Pane supporting structure



R. F. BLANCHFORD PANE SUPPORTING STRUCTURE July 16, 1935.

Filed July 12, 1935 Inventor v y torney- Patented July 16, 1935 PATENTV'VIOI'FFICE PANE SUPPORTING STRUCTURE Ronald Fred Blanchford, Clysthydon, England, I

assignor of one-hall to United Gas Industries Limited, London, England a Application July 12, 1933, Serial No. 680,100 In Great Britain April 15, 1932 Claims. (Cl. -565) This invention relates to cooking stoves or ovens and especially to so-called gas and electric cookers. The invention has among its objects to provide such stoves or ovens with transparent panels not liable to fracture under the variable temperature conditions of use nor under the same conditions to allow leakage of moisture laden air into the space between the panes, by which moisture is deposited on the inner face of the outermost pane thus obscuring vision of the contents of the stove or oven in cooking.

The invention has also among its objects to accommodate the transparent panels and ancillary parts whereby the doors are relatively light and the thickness of the door or mounting frame relatively small.

According to the invention the panels are mounted within the door or within a wall of the stove or oven by means of a quadrilateral mounting frame having an inwardly extending flange forming at opposite sides faces against which the respective inner faces of the panes constituting the panel may lie, suitable packing being interposed between the faces of the flange and the respective panes, and the quadrilateral frame being held in position and pressure imposed to maintain tight joints at the jointing faces by means of a lining frame mounted at the inner face of the door or wall, the lining frame being maintained in position by means of a number of screw-threaded pins which pass through external lugs or through an outwardly extending flange, integrally formed upon the frame. By such means the respective panes of the panel may be closely juxtaposed with anair space of minimum depth between and panes of a small thickness may be used. The total thickness of the door or the supporting frame is thus also determined by a minimum depth of the supporting frame within which the panes and ancillary parts are enclosed. The transparent panes forming the panels are advantageously produced from highly refractory glass having a low coeflicient of expansion such as fused transparent silica, or glass such as that of which cooking vessels are now commonly made, for example that known on the market under the registered trade mark Pyrex or glass such as that known under the registered trade mark Armourplate. By the use of such material and by suitable mounting of the panes liability of fracture of the glass and consequent leakage of moisture laden air into the air spaces between the panels is minimized or prevented.

' The invention comprises the features which are hereinafterdescribed.

In order that the invention may be more clearly understood reference is made to the accompanying drawing in which 0 Figure 1 is a front elevational view of a gas cooking stove or oven constructed according to the invention.

Figure 2 is a detailed sectional view illustrating the manner in which the transparent panel is 10 secured to the door or the lateral walls of the stove or oven.

Like parts are designated by similar reference characters.

Referring to the accompanying drawing a repl5 resents the door of acooking stove and b are the transparent panes.

In carrying the invention into effect according to the illustrated construction the. door a is provided as a rectangular frame a of curvilinear 2 form and as indicated'in Figure 1 is hinged to the casing of the cooking stove at o The frame a is provided with a central aperture within which extend two transparent panes b of refractory glass having a low coefll'cient of expansion such as transparent fused-silica'or of the kind now commonly used for the manufacture of cooking vessels or dishes as for example glass known on the market as Pyrex glass, but a glass of the kind known as Armourplate glass is preferred. The glass panes b are advantageously provided of the same dimensions and of thickness 'of from $4," or less to A" or more, and are coincidently disposed and maintained apart (for example inch apart) within the frame a as shown clearly in Figure 2, by means of a metal mounting frame 0 of a shape and dimensions determined by the frame a and conveniently secured to the frame a by a metal clamping or lining frame I and screws d. The ends of the screws d pass 40 through holes in determined position in the frame 0 and into screw-threaded holes in coincident position in the frame a The frame 0 may be integrally formed with an outwardly extending continuous flange or with equivalent'separate lugs c and the frame may be formed with an integral inwardly extending continuous flange 0 by which channels are formed between the metal clamping or lining frame I and the flange c of the frame 0 and between the frame c and the adjacent part of the door frame a for the reception of the respective panes b of glass constituting the panel. The glass panes b are secured in position in the door frame a with gas tight joints by the insertion between them and the frame 0 55 of asbestos packing stripse which lie against the lateral faces of the inwardly extending flange c and in addition packing strips may be applied respectively between the inner face of the inner pane of glass and the inner face of the lining frame 1 and between the outer face of the outer pane of glass and the adjacent inner face of the door or supporting frame a Or again single packing strips of asbestos or other material formed to a substantially U-shaped cross-section may be used to embed the respective glass panes 12 near their edges within the channels respective ly formed by the frame c and the adjacent edges of the rectangular door frame a and of the lining frame I; or again any other refractory packing or luting may be applied within the channels provided for the reception of the sheets of glass within the door frame a as aforesaid, by means of which effective gas-tight joints may be secured. It will however be understood that packing strips e applied on the respective jointing faces of the flange c are effective and are preferred.

By such means the inner pane of glass is in the use of the cooking stove or oven, sufliciently heated to avoid the condensation of moisture upon it, while the air space between is always maintained closed against the access of moisture from the stove or oven or from outside. In this way the panes of glass are maintained transparent and without liability of the deposit of moisture thereon.

Such transparent panels consisting of a double wall of refractory glass may be provided in the manner described in the lateral walls of the: stove casing or oven or in both the walls and the door, it being understood that the intermediate air space serves as insulation.

It will be understood that otherwise than providing the door for the accommodation of elements in the panels spaced apart with an intermediate air space and mounted with gas tight joints in the manner described, the door may be provided as is usual and with means for fastening the door in its closed position.

According to modifications, the stove or oven may be provided with more than one transparent panel, or a transparent panel may be provided in the top wall or in any other position convenient for the illumination of the contents of the oven from an outside source. Or the door or walls may be provided with two transparent panels, one disposed above or beside the other. Such an arrangement of two' panels may be similarly provided in the lateral walls of the stove. The space between the glass sheets or panes or between the walls of the panel may be formed gas-tight and may be evacuated or partially evacuated.

I claim:-

1. A pane supporting structure comprising an outer frame member having a front wall and an outer side wall and normally open at its back and inner side, outer and inner panes having edge portions extending into the inner side of the outer frame member, an inner frame member supported in said outer frame member outwardly beyond said edge portions of the panes and having an outwardly extending flange and an inwardly extending flange, the latter interposed between the said panes, a clamping member closing the back of the outer frame member, and fastening means engaging said outer and clamping frame members and passing through the outwardly extending flange of the inner frame member to clamp said framemembers andpanes together.

2. A pane supporting structure comprising an outer frame member having a front wall and an outer side wall and normally open at its back and inner side, outer and inner panes having edge portions extending into the inner side of the outer frame member, an inner frame member disposed within the outer frame member outwardly beyond the said edge portions of the panesand having an inwardly extending flange interposed between and spacing said panes, the front wall of the outer frame member having a clamping surface engaging the outer face of the outer pane and outer side of the inner frame member, a clamping frame member closing the open back of the outer frame member and engaging the inner side of the inner frame member and outer face of the inner pane, and fastening means rigidly connecting said outer and clamping frame members and passing throughthe inner frame member to positively connect all three frame members and clamp said frame members and panes together.

3. A pane supporting structure comprising an outer frame, outer and inner. panes, an inner frame disposed within the outer frame outwardly beyond the edges of the panes and having an inwardly extending flange interposed between and spacing said panes, the outer pane and outer side of the inner frame, a clamping frame disposed opposite said surface and enga ing the inner side of the' inner frame and outer face of the inner pane, said inner frame being also provided with an outwardly extending fastening portion, and

fastening means connecting the clamping framewith the outer frame and also passing through the said fastening portion of the inner frame so as to rigidly clamp said frames and panes together.

4. Apane supporting structure comprising a channeled or recessed outer frame member having a front wall and an outer side wall and being between and spacing said panes, an outwardly extending flange and opposite lateral flanges, the said outer frame member having its front wall provided with a clamping surface against which the outer side of the outer pane and one of said lateral flanges of the inner frame member bear, a clamping frame member closing the back'of the outer frame member and bearing against the other lateral flange of the inner frame member and the outer side of the inner pane, and fastening means connecting the clamping frame member and the outer frame member and passing through said outwardly extending flange of the inner frame member so as to rigidly connect and clamp said frame members and panes together.

5. A pane supporting structure comprising an outer frame of substantially L-form in cross-section presenting a front wall and an outer side wall and being normally open at its back and inner side, inner and outer panes having edge portions extending into the inner side of the outer frame member, an inner frame of substantially cruciform shape disposed within the outer frame outwardly beyond the edges of the panes and comprising a body portion having an inwardly extending flange interposed between and spacing said panes, an outwardly extending flange and opposite laterally extending flanges, the said front wall of the outer frame having a clamping surface against which the outer side of the outer pane and one of the lateral flanges of the inner I frame member abut, a clamping frame member closing the back of the outer frame and bearing against the outer face of the inner pane and the other lateral flange of the inner frame mem- RONALD FRED BLANCHFORD. 

